Featured Research

from universities, journals, and other organizations

World's smallest wrench puts new twist on microscopic manipulation; Harnesses laser light's ability to gently push and pull

Date:
December 3, 2012
Source:
The Optical Society
Summary:
Harnessing laser light's ability to gently push and pull microscopic particles, researchers have created the fiber-optic equivalent of the world's smallest wrench. This virtual tool can precisely twist and turn the tiniest of particles, from living cells and DNA to microscopic motors and dynamos used in biological and physical research.

This shows a fiber-optically trapped and rotated human smooth muscle cell in the center of two transversely offset fibers (20 mW in each arm).
Credit: Optics Letters

Harnessing laser light's ability to gently push and pull microscopic particles, researchers have created the fiber-optic equivalent of the world's smallest wrench. This virtual tool can precisely twist and turn the tiniest of particles, from living cells and DNA to microscopic motors and dynamos used in biological and physical research.

This new twist on controlling the incredibly small, developed by physicists at The University of Texas at Arlington, will give scientists the ability to skillfully manipulate single cells for cancer research, twist and untwist individual strands of DNA, and perform many other functions where microscopic precision is essential. The authors describe their new technique, which they dub a fiber-optic spanner (the British term for a wrench), in a paper published today in the Optical Society's (OSA) journal Optics Letters.

The innovation that distinguishes this technique from other optical tools is that it can, for the first time, spin or twist microscale objects in any direction and along any axis without moving any optical component. It's able to do this because it uses flexible optical fibers rather than stationary lasers to do the work. This has the added benefit that the optical fibers can be positioned inside the human body, where they can manipulate and help study specific cells or potentially guide neurons in the spinal cord.

Rather than an actual physical device that wraps around a cell or other microscopic particle to apply rotational force, or torque, the fiber-optic spanner is created when two beams of laser light -- emitted by a pair of optical fibers -- strike opposite sides of the microscopic object.

Individual photons impart a virtually imperceptible bit of force when they strike an object, but an intense beam of laser light can create just enough power to gently rotate microscopic particles. "When photons of light strike and then get reflected back from an object, they give it a small push from an effect called scattering forces," explains Samarendra Mohanty, assistant professor of physics at The University of Texas at Arlington and lead author of the study. This technique is already used to perform optical "tweezing," which can move an object forward and backward along a straight line. "Optical tweezing is useful for biomedical and microfluidic research," said Mohanty. "But it lacks the control and versatility of our fiber optic spanner, especially when it comes to working deep inside."

In the team's new optical spanner, the optical fibers use laser beams to first trap an object and then hold it in place. By slightly offsetting the optical fibers, the beams are able to impart a small twisting force, which causes the object to rotate in place. Depending on the positioning of the fibers, it is possible to create rotation along any axis and in any direction. This greatly enhances researchers' ability to study and image cells and groups of cells for biological research and medical analysis.

In their research, Mohanty and graduate student Bryan Black used their new technique to rotate and shift human smooth muscle cells without damaging them. Demonstrating that the technique may have both clinical and laboratory uses.

For example, the spanner could rotate cells in a microfluidic analysis, image them with tomography, and then move them aside to allow the analysis of subsequent cells in the flow.

The technique could also be used to rotate single cells to determine by their spin if they are normal or cancerous. It could also help examine embryos to aid in in-vitro fertilization. It could mix or pump the fluids in lab-on-a-chip devices, or move and rotate micro-spheres attached to the opposite ends of a DNA strand to stretch and uncoil the molecule, allowing it to be sequenced more efficiently. In a follow-up paper to be published in Applied Physics Letters, Mohanty describes how this method can be used to rotate and fluorescently scan an object, which would reveal details about its chemical properties.

Non-medical macroscopic uses for the tool are also possible. "I envision applications in the direct conversion of solar energy to mechanical energy, rotating large, macroscopic objects using this technique," Mohanty says. This would "simulate an environment in which photons radiated from the Sun could propel the reflective motors in solar sails, a promising future technology for deep-space travel."


Story Source:

The above story is based on materials provided by The Optical Society. Note: Materials may be edited for content and length.


Journal Reference:

  1. Bryan J. Black, Samarendra K. Mohanty. Fiber-optic spanner. Optics Letters, 2012; 37 (24): 5030-5032 [link]

Cite This Page:

The Optical Society. "World's smallest wrench puts new twist on microscopic manipulation; Harnesses laser light's ability to gently push and pull." ScienceDaily. ScienceDaily, 3 December 2012. <www.sciencedaily.com/releases/2012/12/121203093417.htm>.
The Optical Society. (2012, December 3). World's smallest wrench puts new twist on microscopic manipulation; Harnesses laser light's ability to gently push and pull. ScienceDaily. Retrieved July 24, 2014 from www.sciencedaily.com/releases/2012/12/121203093417.htm
The Optical Society. "World's smallest wrench puts new twist on microscopic manipulation; Harnesses laser light's ability to gently push and pull." ScienceDaily. www.sciencedaily.com/releases/2012/12/121203093417.htm (accessed July 24, 2014).

Share This




More Matter & Energy News

Thursday, July 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

TSA Administrator on Politics and Flight Bans

TSA Administrator on Politics and Flight Bans

AP (July 24, 2014) TSA administrator, John Pistole's took part in the Aspen Security Forum 2014, where he answered questions on lifting of the ban on flights into Israel's Tel Aviv airport and whether politics played a role in lifting the ban. (July 24) Video provided by AP
Powered by NewsLook.com
Creative Makeovers for Ugly Cellphone Towers

Creative Makeovers for Ugly Cellphone Towers

AP (July 24, 2014) Mobile phone companies and communities across the country are going to new lengths to disguise those unsightly cellphone towers. From a church bell tower to a flagpole, even a pencil, some towers are trying to make a point. (July 24) Video provided by AP
Powered by NewsLook.com
Algonquin Power Goes Activist on Its Target Gas Natural

Algonquin Power Goes Activist on Its Target Gas Natural

TheStreet (July 23, 2014) When The Deal's Amanda Levin exclusively reported that Gas Natural had been talking to potential suitors, the Ohio company responded with a flat denial, claiming its board had not talked to anyone about a possible sale. Lo and behold, Canadian utility Algonquin Power and Utilities not only had approached the company, but it did it three times. Its last offer was for $13 per share as Gas Natural's was trading at a 60-day moving average of about $12.50 per share. Now Algonquin, which has a 4.9% stake in Gas Natural, has taken its case to shareholders, calling on them to back its proposals or, possibly, a change in the target's board. Video provided by TheStreet
Powered by NewsLook.com
Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins